Is Pacific madrone (Arbutus menziesii) suitable for outdoor bonsai in a large tub? It is native to my area and I love it very much but have no space for it in the open ground (mature madrones are very large).

I came across only one mention of it in all my Googling, which was that it was only suitable for "larger bonsai". The tub I have is an old, deep concrete sink, I would say 20-25 gallon size, with good drainage.

If I can do it, where do I get it? I haven't had much luck finding seedlings available, do I have to grow it from seed?

Thanks

Kristin